1. Field of the Invention
The present invention relates generally to an exercise machine, and more particularly to an elliptic motion exercise machine. In the path of motion, user's toe and heel have the same speed.
2. Description of the Related Art
Exercise machines provide various paths of motion that user may exercise various portions muscles thereon. For example, stepper provides vertical reciprocating motion, bike provides circular motion, air walker provides horizontal reciprocating motion, and elliptical trainer provides elliptical motion.
U.S. Pat. No. 5,242,343, issued to Miller, disclosed an elliptical trainer, which includes a frame, on which a rotational motion mechanism, a reciprocating motion mechanism and a pair of foot engaging links connected to the rotational motion mechanism and the reciprocating motion mechanism are provided. The rotational motion mechanism generates a circular motion, and the reciprocating motion mechanism generates a linear or curved reciprocating motion. User stands on the foot engaging links may exercise along an elliptic motion. When user takes exercise on Miller's trainer, the speeds of user's heels are greater than that of toes.